Tens of thousands of residents in suburban Songjiang District are expected to have safe drinking water from their taps again today after chemical pollutants were discharged last Thursday into a creek from where water supplies are drawn.

But residents of nearby districts where tap water was turned on again earlier complained that the water still had a chemical smell.

The carcinogenic pollutants discharged into Jueshigang Creek were mostly benzene compounds, including styrene.

Tap water, which was cut off Friday, was to resume flowing to affected areas of Songjiang District around midnight last night.

Residents in Maogang Town, Songjiang, are advised to let their taps run for 20 to 30 minutes to flush out any polluted water once operations resume.

About 30,000 residents in the town had to line up for the water delivered by fire engines for the past two days as water in Maogang Water Plant was still undergoing treatment.

Bottled water also was delivered to other nearby areas, but even though tap water service had been restored, residents complained about its odor.

“I still smell gas from the running water,” a resident who lives in Jinshan’s Zhujing Town posted on the Internet yesterday. “How are we supposed to drink the water?” asked the person, who declined to give a name.

The Jinshan District government said water authorities had conducted 33 tests from Saturday to Sunday at a water treatment plant and the water is safe to drink. No unsafe levels of pollutants were detected during the tests, officials said.

As of late yesterday, water authorities said water from Jinshan and Fengxian water treatments plants, close to the affected creek, “did not completely remove the smell” of chemicals. However, they said it should be gone soon.

“City water authorities will continue to monitor the water quality each hour to ensure safety,” an official said.

The discharge was caused by a leaky valve on a chemical transport boat during loading at a dock in Jinshan.

Altogether 23 locals were hospitalized, mainly due to inhaling benzene compounds, since the incident broke out on Thursday night. Five remained in the hospital yesterday, all in stable condition.

Four people, three on board the vessel and a director of the Jinwei Chemicals Co, have been detained, with another three suspects released on bail, officials said. Authorities found that the dock was not licensed for handling chemicals.

Affected residents in Jinshan will see their water bills cut in half for the month, district government announced yesterday evening. Songjiang District government said residents in Songjiang will also see similar discounts, but they didn’t specify the amount.